1986 Corvette bogs down
Thread Starter
Cruising
Joined: Jun 2010
Posts: 12
Likes: 0
1986 Corvette bogs down
I have an 86 Vette with 26,000 miles on it. When the car is cold it runs great. But as soon as it warms up it starts to run not so good. When its warmed up and i give it gas while I'm driving it it bogs down. But when I first run it and the engine is cold it will not do this it runs great. Also when the car is in park and I rev the engine even when warmed up it seems to run great. It is just when the engine is warmed up and I'm driving it that it bogs down when you give it to much gas. I have replaced the fuel pump and filter on it and also ECM is new. I have also put a new catalytic converter, but the problem still remains. I get no check engine warnings either so I really don't know what it could be. Maybe a bad MAF. Any help will be appreciated. Thanks.
Burning Brakes
Joined: Jun 2008
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From: New Smyrna Beach Florida
Instructor
Joined: Jun 2010
Posts: 112
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From: phx az
on the passenger side of the motor on the block between exhaust manifold runners , there are 2 i think the top one is a coolant bottom is knock . they say its easier to get at from the bottom of car. and use sum vise grips on the round part at the same time as u crank on the bolt. it helps it come out in 1 piece
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From: Merritt Ils Fl
Racer
Joined: Apr 2011
Posts: 296
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From: Tipp City Ohio
I have an 86 Vette with 26,000 miles on it. When the car is cold it runs great. But as soon as it warms up it starts to run not so good. When its warmed up and i give it gas while I'm driving it it bogs down. But when I first run it and the engine is cold it will not do this it runs great. Also when the car is in park and I rev the engine even when warmed up it seems to run great. It is just when the engine is warmed up and I'm driving it that it bogs down when you give it to much gas. I have replaced the fuel pump and filter on it and also ECM is new. I have also put a new catalytic converter, but the problem still remains. I get no check engine warnings either so I really don't know what it could be. Maybe a bad MAF. Any help will be appreciated. Thanks.
Did you ever figure out your problem? Does anyone have any ideas or experience with this issue?
Thanks!!!
Last edited by Tony A.; May 22, 2011 at 11:22 PM.
Le Mans Master
Joined: Oct 2006
Posts: 6,842
Likes: 285
From: Palmdale CA
I'd say fuel injectors too. The early C4 Multecs are junk. I don't care if it has only 26K on it. Once we replaced them with the rebuilt injectors from FIC, the 87' ran totally different. And even if it doesn't, when you fix, what you fix, the car will run much better. There are many of us who've done the injector swap and it works!
Thread Starter
Cruising
Joined: Jun 2010
Posts: 12
Likes: 0
If you can believe it my Vette still runs bad. I don't know the last thing to try is injectors. I had my ecm replaced so maybe their is a wiring issue. I replaced my knock sensor to no avail. The times when it does run right it's amazing. I'll keep you up to date. By the way is it possible that there could be rust in the gas tank even though it's made of rubber?
Racer
Joined: Apr 2011
Posts: 296
Likes: 1
From: Tipp City Ohio
If you can believe it my Vette still runs bad. I don't know the last thing to try is injectors. I had my ecm replaced so maybe their is a wiring issue. I replaced my knock sensor to no avail. The times when it does run right it's amazing. I'll keep you up to date. By the way is it possible that there could be rust in the gas tank even though it's made of rubber?
Good luck with your issues. If you ever figure yours out, let me know. I will do the same.
Le Mans Master
Joined: Oct 2006
Posts: 6,842
Likes: 285
From: Palmdale CA
If you can believe it my Vette still runs bad. I don't know the last thing to try is injectors. I had my ecm replaced so maybe their is a wiring issue. I replaced my knock sensor to no avail. The times when it does run right it's amazing. I'll keep you up to date. By the way is it possible that there could be rust in the gas tank even though it's made of rubber?
Racer
Joined: Apr 2011
Posts: 296
Likes: 1
From: Tipp City Ohio
If you can believe it my Vette still runs bad. I don't know the last thing to try is injectors. I had my ecm replaced so maybe their is a wiring issue. I replaced my knock sensor to no avail. The times when it does run right it's amazing. I'll keep you up to date. By the way is it possible that there could be rust in the gas tank even though it's made of rubber?
I replaced my fuel pump and fuel sock. Took all of 30 mins and $90, going with AC Delco parts. I've been struggling with this for 6 weeks and finally got into the tank. It had a lot of small debris. I cleaned out what I could and put in the new parts and BAM, it works!
Good luck finding your issue.
